Grade 4 - Progress in Mathematics

Step 1:Multiplyto find the cost of

3 jumbo magnets. 3 
$ 1.19

Step 2:Divideto find the cost of

1 magnifying glass. $ 5.78  2

Step 3:Addto find the total cost.

Step 4:Subtractto find Hector’s change from $ 10.

Estimate to check: cost of magnets 3 
$1 $3

cost of magnifying glass $6  2 $3

$ 10 $6 $4 change

The answer $ 3.54 is close to the estimate of $ 4.

Visualize the facts of the problem.

Facts: 3 jumbo magnets—$ 1.19 each

1 magnifying glass—2 for $ 5.78

paid $ 10

Question: How much change did Hector get?

Hector bought 3 jumbo magnets and

1 magnifying glass at the science sale.

How much change did he get from $10?

Problem-Solving Strategy:

Use More Than One Step

13-11

Science Sale

mini-magnet $ .45 each

jumbo magnet $ 1.19 each

magnifying

glass $ 5.78 for 2

Step 1 Step 2 Step 3 Step 4

9 9

2 1 1 0 10 10 10

$1.1 9 $2.8 9 $3.5 7 $1 0.0 0


 3 2 
$ 5 .7 8 2.8 9  6.4 6

$3.5 7  4 $6.4 6 $ 3.5 4

1 7

3 magnets 1 6 total Hector’s

 1 8 cost change

1 8

1 magnifying

glass

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